popper vs hook size

[FishnDave]

My experience is that the popper size isn't the same as the hook size. I bought (I think?) size 4 bass popper bodies, and they seem to match up perfectly with a Size 10 Umpqua "Special Use" hook, like the style in your bottom hook picture.

But...in my case, I can't figure out why this is considered a size 10 hook, because they are plenty big...way way way bigger than any standard size 10 hooks? I figured it had something to do with the "Special Use" designation?